digdeep

凡是过去,皆是序幕。Read the fucking manual and source code.

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虽然MySQL的存储过程,一般情况下,是不会使用到的,但是在一些特殊场景中,还是有需求的。最近遇到一个sql server向mysql迁移的项目,有一些sql server的存储过程需要向mysql迁移。所以进行复习了一下。下面是一些存储过程的例子。

1. 例子1

DELIMITER //
DROP PROCEDURE IF EXISTS loginandreg //

CREATE PROCEDURE loginandreg(
   OUT userId     BIGINT,
   IN user_Pwd                          VARCHAR(32),
   IN user_MobileCode                   VARCHAR(16),
   IN user_RegIP                        VARCHAR(16)
)
BEGIN

DECLARE cnt  BIGINT DEFAULT 0;
DECLARE cnt2  BIGINT DEFAULT 0;
DECLARE outid BIGINT DEFAULT -1;

SELECT COUNT(*) INTO cnt FROM Users u WHERE u.user_MobileCode=user_MobileCode;

IF cnt > 0 THEN
    SELECT COUNT(*) INTO cnt2 FROM Users u WHERE u.user_MobileCode=user_MobileCode AND u.user_Pwd=user_Pwd;
    
    IF cnt2 > 0 THEN
        SELECT u.userId INTO outid FROM Users u 
        WHERE u.user_MobileCode=user_MobileCode AND u.user_Pwd=user_Pwd LIMIT 1;
    ELSE    
        SELECT -1 INTO outid;
    END IF;
    
    SELECT outid INTO userId;
ELSE 
    INSERT INTO Users(user_Pwd,user_MobileCode,user_Visibility,user_Level,user_RegTime,user_RegIP,
user_Collecter,user_Collected)
VALUES (user_Pwd,user_MobileCode,6,6,NOW(),user_RegIP,0,0); SET userId=LAST_INSERT_ID(); SELECT userId; END IF; END // DELIMITER ;

知识点

1)参数分为 in, out 类型,即输入类型和输出类型;

2)select xx into varible from table where ... 句式:

     SELECT COUNT(*) INTO cnt FROM Users u WHERE u.user_MobileCode=user_MobileCode;

3)if cnt > 0 then ... elseif cnt =0 then ... else ... end if;

    if 语句注意带有 then 关键字和 end if 结束关键字。

4)获取 insert 语句的主键set userId=last_insert_id(); select userId;

   select last_insert_id() into userId; 也是可以的。

5)mysql客户端 如何调用该存储过程:

CALL loginandreg(@userId,'123456','18357xxx7','127.0.0.1');
SELECT @userId;

 最后的 select @userId 就是存储过程的 out 类型参数返回的结果。

6) 上面的例子,还可以使用 if exists ( select from ...) 语句和 FOUND_ROWS() 函数 来优化一下:

DELIMITER //
DROP PROCEDURE IF EXISTS loginandreg //

CREATE PROCEDURE loginandreg(
    OUT userId     BIGINT,
    IN user_Pwd                          VARCHAR(32),
    IN user_MobileCode                   VARCHAR(16),
    IN user_RegIP                        VARCHAR(16)
)
BEGIN
IF EXISTS(SELECT * FROM Users u WHERE u.user_MobileCode=user_MobileCode) THEN
    SELECT u.userId INTO userId FROM Users u WHERE u.user_MobileCode=user_MobileCode AND u.user_Pwd=user_Pwd;    
    IF FOUND_ROWS() < 1 THEN
        SELECT -1 INTO userId;
    END IF;
ELSE 
    INSERT INTO Users(user_Pwd,user_MobileCode,user_Visibility,user_Level,user_RegTime,user_RegIP,
user_Collecter,user_Collected)
VALUES (user_Pwd,user_MobileCode,6,6,NOW(),user_RegIP,0,0); SELECT LAST_INSERT_ID() INTO userId; END IF; END // DELIMITER ;

2. 例子2

DELIMITER //
DROP PROCEDURE IF EXISTS mingRenTangJiangLi //
CREATE PROCEDURE mingRenTangJiangLi()
BEGIN
DECLARE total_level,role_id,ming_ren_level,ming_ren_type,
                fuben_times,tiaozhan_times,duobei_shijian,no_more_data INT DEFAULT 0;

DECLARE my_cursor CURSOR FOR SELECT playerRoleId,`level`,type from mingrentang;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_data = 1;

OPEN my_cursor;
FETCH my_cursor INTO role_id,ming_ren_level,ming_ren_type;

REPEAT
set total_level = ming_ren_level + 10 * (ming_ren_type-1);
set fuben_times = total_level / 2;
set tiaozhan_times = total_level /3;
set duobei_shijian = 10 * total_level;
select total_level,fuben_times,tiaozhan_times,duobei_shijian;

update player_role set hufu=hufu+1000,paihangbangNumber=paihangbangNumber+tiaozhan_times,
                duobeiShiJian=duobeiShiJian+duobei_shijian,fubenTimes=fubenTimes+fuben_times;

FETCH my_cursor INTO role_id,ming_ren_level,ming_ren_type;
UNTIL no_more_data = 1
END REPEAT;

CLOSE  my_cursor;

END //
DELIMITER ;

知识点

1)该例子演示了游标的用法:

DECLARE my_cursor CURSOR FOR SELECT playerRoleId,`level`,type from mingrentang;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_data = 1;

定义了游标语句,也说明了游标循环结束时设置的标志:SET no_more_data = 1;

OPEN my_cursor;
FETCH my_cursor INTO role_id,ming_ren_level,ming_ren_type;

打开游标,从游标中获取值。

REPEAT
......
FETCH my_cursor INTO role_id,ming_ren_level,ming_ren_type;
UNTIL no_more_data = 1
END REPEAT;
repeat 循环 直到 no_more_data = 1UNTIL no_more_data = 1,然后结束循环 END REPEAT;
最后关闭游标 close my_cursor;

因为上面在定义游标时,指明了,没有数据时设置了 no_more_data = 1,所以这里使用 UNTIL no_more_data = 1 来退出repeat

2)判断相等是使用 = ,而不是 == ,赋值操作是使用 set var=xxx; :set fuben_times = total_level / 2;

3)循环: repeat ... until ...  end repeat;

3. Java 如何调用存储过程

1)hibernate调用存储过程:

    /*
         * 调用无参数的存储过程,传入存储过程名字
         */
    public int callProcedure(final String procedureName)
    {
            int count = (Integer)this.getHibernateTemplate().execute(
                new HibernateCallback(){
                public Object doInHibernate(Session session) throws HibernateException, SQLException {
                    String procedureSql = "{call "+ procedureName +"()}";
                    Query query = session.createSQLQuery(procedureSql);
                    Integer num = query.executeUpdate();
                    return num;
                }
            });
            return count;
    }

2)ibatis 调用mysql 存储过程:

    @Override
    public Long loginAndRegByProcedure(String user_Pwd, String user_MobileCode, String user_RegIP){
        Long userId = null;
        HashMap<String,Object> paramMap = new HashMap<String,Object>();  
        paramMap.put("userId", userId);  
        paramMap.put("user_Pwd", user_Pwd);  
        paramMap.put("user_MobileCode", user_MobileCode);  
        paramMap.put("user_RegIP", user_RegIP);  
        
        this.getSqlMapClientTemplate().queryForObject("Users.loginAndRegByProcedure", paramMap);  
        return (Long)paramMap.get("userId"); 
    }

对应的xml 文件配置:

  <parameterMap id="pro_pram_Map" class="java.util.Map">
      <parameter property="userId" javaType="java.lang.Long" jdbcType="BIGINT" mode="OUT"/>
      <parameter property="user_Pwd" javaType="java.lang.String" jdbcType="VARCHAR" mode="IN"/>
      <parameter property="user_MobileCode" javaType="java.lang.String" jdbcType="VARCHAR" mode="IN"/>
      <parameter property="user_RegIP" javaType="java.lang.String" jdbcType="VARCHAR" mode="IN"/>
  </parameterMap>
  <procedure id="loginAndRegByProcedure" parameterMap="pro_pram_Map">
      {call loginandreg(?, ?, ?, ?)}
  </procedure>

存储过程的参数的类型,是在xml文件中说明的。

3) JDBC 调用mysql 存储过程:

    public Long loginAndRegByProcedure2(String user_Pwd, String user_MobileCode, String user_RegIP){
        Connection conn = DbUtil.getConnection();
        CallableStatement cstmt =  conn.prepareCall("{call loginandreg(?, ?, ?, ?)}");
        cstmt.setString(2, user_Pwd);
        cstmt.setString(3, user_MobileCode);
        cstmt.setString(4, user_RegIP);
        cstmt.registerOutParameter(1, java.sql.Types.BIGINT);
        cstmt.execute();
        return cstmt.getLong(1);
    }

输入参数:cstmt.setString(2, user_Pwd);

输出参数:cstmt.registerOutParameter(1, java.sql.Types.BIGINT);

4)mybatis 调用mysql存储过程:

mapper 接口

public interface UserMapper {
    Long loginAndRegByProcedure(Map<String, Object> param);

 xml 配置文件

  <select id="loginAndRegByProcedure" parameterType="java.util.Map" statementType="CALLABLE" resultType="long">  
      {call loginandreg(
              #{userId,jdbcType=BIGINT,mode=OUT},
              #{user_Pwd,jdbcType=VARCHAR,mode=IN},
              #{user_MobileCode,jdbcType=VARCHAR,mode=IN},  
              #{user_RegIP,jdbcType=VARCHAR,mode=IN}
          )
       }
  </select>

注意: statementType="CALLABLE" resultType="long" 和 mode=OUT

service 层调用mapper接口:

        Long userId = null;
        HashMap<String,Object> paramMap = new HashMap<String,Object>();  
        paramMap.put("userId", userId);  
        paramMap.put("user_Pwd", user_Pwd);  
        paramMap.put("user_MobileCode", user_MobileCode);  
        paramMap.put("user_RegIP", user_RegIP);       
userId=userMapper.loginAndRegByProcedure(map);

 

posted on 2015-09-16 17:56  digdeep  阅读(3387)  评论(0编辑  收藏  举报
不懂数据库和Web安全的架构师不是一个好的程序员。